| 摘要 |
Glass of high resistance to attack by water and chemicals and suitable for the manufacture of fibres contains silica, magnesia, alumina, baryta, lime, boric oxide, zinc oxide, zirconia, and alkali metal oxides in specified proportions, the balance, if any, consisting of other compatible constituents. Ranges lie, in weight percentages, in SiO2 57-60; Fe2O3 0-1; Al2O3 6-7.5; CaO 5-6.5; MgO 2-2.5; Na2O 11-13; K2O 2-3; B2O3 5-6; BaO 1-2; ZrO2 1.5-2.5; F 0.5-1.5; ZnO 0.7-1.5. |
